Was the tank full when you started you check? did the 6 gallons fill it to the brim?

As you can see on Motabilities web site the 1.4 120BHP claims 47.9 Miles to the gallon, the 1.4 100bhp is 46.3.
You have a fairly heavy car there and a small BHP, meaning the engine is working harder to pull the car along.
It would have been better (Hindsight is such a useful thing (not))
to go for the 1.7 Deisel 130 BHP and a claimed 53.3 with an AP of £349

more layout at the start, but over three years a cost saving.
pDid you try any other cars before choosing? what were their MPG's?

i would have gone for a bigger car if i could of but i was wanting to put my son on insurance as second driver( hes under 25 ) incase i fell ill at least then my wife could still get about in it. i was put off getting a diesel due to being advised that the dpf filter problems. dealer manager said all this running the engine in isnt needed it should be ok. i did test drive it before getting it but didnt realise petrol fuel consumption was bad on the merivas. i htink the law needs changing on what manufacturers claim that cars can do. motabilty have said that i can change it after a month if it doesnt improve

i would have gone for a bigger car if i could of but i was wanting to put my son on insurance as second driver( hes under 25 ) incase i fell ill at least then my wife could still get about in it. i was put off getting a diesel due to being advised that the dpf filter problems. dealer manager said all this running the engine in isnt needed it should be ok. i did test drive it before getting it but didnt realise petrol fuel consumption was bad on the merivas. i htink the law needs changing on what manufacturers claim that cars can do. motabilty have said that i can change it after a month if it doesnt improve

There is a lot of nonsense talked about DPFs. So long as you regenerate them when the indicator goes orange and before it goes red, thewy are fine, and thats just a blast down the motorway (I know as my last job was warranty recovery at JLR)
The fact is its due to the law that the figures as shown are used. The figures have to be confirmed by an independant body

I do wonder if as you have not filled up the tank, driven a few miles then refilled that your estimation can be off, as you are basing it on a fuel sender unit and the mileometer.
When you have ;ess fule in tghe tank, near empty sender floats can give strange readings.

I have a picasso 1.6 diesel automatic and regularly get 40-45 mpg.I have had this car for 7 months and only have to fill up once a month instead of every 2 weeks when I had a Zafira.Best choice of car I have ever made

gonna fill car up on wednesday and do a check on it after doing about 100 miles and see what mpg i get then seems to be only way to do it. i wish i had a trip computer on it as it would have saved any hassle on what consumption its doing. will let you know by next friday or sooner i hope. i will then leave the readings for some one to clarify what mpg they think i,m getting.
the only thing i do find confusing is honest johns website says my car should be doing 35+ mpg.

the only way to get an accurate mpg reading is a brim to brim filling,trip computers tend to be wide of the mark as they do not actually measure fuel passing through the fuel line,but make a calculation based on road speed/accelarator pressure/engine revs etc.
my last 4 cars with trip computers, 3 read 10 to 15 % optimistic,the other one suprisingly 5 % pessemistic.

just back from blackpool. i filled car to brim went to blackpool for an hour then drove back to petrol station where i filled up again . it only cost me £13.89 to fill it back up again , now based on this the car did 48.1 miles to the gallon and only used 10.07 liters of fuel. but out of the total miles (106.5) . 7 miles was round town the rest was motorway at 60-70 mph.. doing just town now for few days to see what town fuel consumptions like.

i would have gone for a bigger car if i could of but i was wanting to put my son on insurance as second driver( hes under 25 ) incase i fell ill at least then my wife could still get about in it. i was put off getting a diesel due to being advised that the dpf filter problems. dealer manager said all this running the engine in isnt needed it should be ok. i did test drive it before getting it but didnt realise petrol fuel consumption was bad on the merivas. i htink the law needs changing on what manufacturers claim that cars can do. motabilty have said that i can change it after a month if it doesnt improve

So it is true then, it isn't possible to insure an under 25 (policy holder or named driver) on a car above that certain insurance group.